Since I am on Indigo 7 I've had a chance to test the included Reflector service, but it seems to be very slow for me (I'm located in Europe).
I can imagine that the Reflector service is running on a server in the US and that the roundtrip is eating away at the connection speed.
The speed I'm getting with Reflector is making the iPhone app unusable for me.
I am wondering though, in terms of security, would a VPN service on my iPhone offer me the same (or similar) kind of security ?